1. Field of the Invention
The present invention generally relates to a technology for synthesizing a plurality of images photographed by a plurality of cameras. More specifically, the present invention relates to a device that uses an image of the area surrounding a vehicle to detect the approach of other vehicles and the like.
2. Background Information
When photographing with a plurality of electronic cameras (e.g., CCD cameras), the color and brightness of the images of the same region will not necessarily match because of individual differences in the cameras and the positions of the cameras. Therefore, when the images picked up by a plurality of cameras are synthesized into a single image, the synthesized portions (seams) require special processing. Japanese Laid-Open Patent Publication No. 11-55682 describes a technology for making the differences in lightness and darkness of the synthesized portions inconspicuous. With this technology, the synthesized portions are made inconspicuous by using the average values of the color and brightness obtained by both cameras or using the color and brightness obtained by one of the cameras as the color and brightness at the portion where the images of the two cameras overlap.
In view of the above technology, there exists a need for an improved image synthesizing device. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.